Oppenheim and Putnam

For an early critique of Oppenheim and Putnam s "sweeping" statements, see Schlesinger (1961). 

This is the main issue between those who oppose the idea that actually, we could carry out a unification of sciences by way of actual steps of reduction, and those who take this assumption, at least as an assumption guiding the investigation, to be promising. The former view is discussed at some length in Darden and MauU (1977), a prominent example of the latter is Oppenheim and Putnam (1958). 

A more explicitly mereological account of reduction is offered by Paul Oppen-heim and Hilary Putnam [Oppenheim and Putnam, 1958], who argue that the explanation of the properties of complex systems in terms of the properties of and relations between their parts (microreduction) is a characteristic and fruitful scientific project. Microreduction is mereological because theory T microreduces a theory T2 when the phenomena explained by T2 are explained by Ti, and Ti... 

Nagel, Oppenheim and Putnam saw the explanatory appheation of physical laws to chemistry as the paradigm example of reduction, and it is stiU cited as such. So how accurately does classical reductionism portray the imdoubted explanatory success of physical theory within chemistry Two main examples are cited in the literature (i) the relationship between thermodynamics and statistical mechanics and (ii) the explanation of chemical valence and bonding in terms of quantum mechanics. The former reduction is widely presumed to be unproblematic because of the identification of temperature with mean molecular kinetic energy, but Needham [2009] points out that temperature can be identified with mean energy only in a molecular population at equilibrium (one displaying the Boltzmann distribution), but the Boltzmann distribution depends on temperature, so any reduction of temperature will be circular (for a survey of the issues see [van Brakel, 2000, Chapter 5]. 

Oppenheim and Putnam, 1958] P. Oppenheim and H. Putnam. Unity of Science as a Working Hypothesis, in H. Feigl, M. Scriven and G. Maxwell (eds.), Minnesota Studies in the Philosopohy of Science Volume II Minneapolis University of Minnesota Press, 3-36, 1958. 

Oppenheim, P. and Putnam, H. (1958). The unity of science as a working hypothesis. In Minnesota Studies in the Philosphy of Science, eds. H. Feigl, G. Maxwell and M. Scriven. University of Minnesota Press, pp. 3-36. 

Throughout this paper I am using the word entity to mean concrete individual or object . The metaphor of the layer cake is due to Putnam and Oppenheim (1958), who adopted it to argue for a certain kind of reductionism. 

Oppenheim, Paul, and Hilary Putnam. 1958. The unity of science as a working hypothesis. In Concepts, theories, and the mind-body problem, ed. Grover Maxwell, Herbert FeigJ, and Michael Scriven, 3-36. Minneapolis Minnesota University Press. 

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